30 May 97
on the usage of the project. Locks with low volumes
two locks, operation of the dam, and operation of
of commercial traffic and high volumes of recrea-
tional use may be designed for local control capabili-
ties where it is necessary for lock operating personnel
(b) Traffic demand; that is, number of lockages,
to be physically present on the lock wall in order to
annual tonnage, and size of tows.
move to the upstream and downstream control sta-
tions to closely supervise the lockage of small craft.
(c) Types of traffic; that is, commercial tows and
Even though a local control operating system is
selected, the control system should incorporate the
PLC system. Locks with a high volume of commer-
(2) Features to be considered.
cial traffic on main stem river navigation systems
should be designed for a central control station
(a) Operations, maintenance, and administrative
containing centralized supervisory and control
functions should be combined in a single building.
equipment to operate all lock and dam equipment
using automated PLC systems. Locks with intermedi-
(b) The central control station should be located
ate levels of commercial traffic volume can be
above the lock wall to provide maximum visibility for
designed for a combination of local and centralized
viewing lock operations and to keep the operations
control systems, depending on the mix of commercial
above flood elevation.
and recreational traffic. Each project needs to be
analyzed for site-specific conditions during the plan-
(c) The central control station should contain
ning and design of the operating system, considering
monitors for CCTV cameras to observe tow approach,
the factors in Paragraph 3-3.
clearance of the tow from the gates, debris or ice in
the gate recesses, and correct mitering of the gates
before filling or emptying. Radar systems can pro-
b. Control systems. The advantages of PLC
vide location of approaching tows during inclement
systems discussed in Chapter A-2 include both first
and life-cycle costs; the ability to prevent damage to
machinery through more sophisticated monitoring and
(d) A surveillance system should be provided for
control techniques, the flexibility to develop control
security of the installation, especially with a mini-
systems of virtually unlimited complexity, the safety
mum lock staff manning the structure. The security
of the low voltage PLC system versus the high volt-
systems can consist of security fencing, remote elec-
tronic monitoring, alarm systems, motion detectors in
appropriate to design operating systems for major
sensitive areas, CCTV surveillance systems, sound
navigation projects using a PLC operating system in a
monitoring of visitor areas and access points, and
central control station supplemented by fiber-optic
gated entry points that can be activated from the
networks, CCTV, electronic communication, and
central control station. All security systems should
computerized data collection capabilities. For smaller
be controlled from the central control station.
navigation projects, local control PLC capabilities
with provision for future centralized control should be
(e) Provision should be made for centrally oper-
incorporated. RBS's should be considered only when
ating other features of the project such as the dam
there is a demonstrated lack of expertise to design or
gates, power-house equipment, and associated facili-
maintain a PLC system.
ties such as drawbridges.
Central control stations.
d. Local control stations. In cases where the
outcome of the comparative studies does not favor
centralized control, fixed local control stations can be
lock projects should be used when justified, based on
provided. No more than two fixed control stations
the comparison of the cost for a large central control
for a single lock chamber or four for a double lock
structure versus the savings that can be realized over a
chamber should be provided. Only one of the control
more labor-intensive system of local control stations.
stations should be equipped with personnel comfort
Factors to be considered are:
facilities such as the bathroom and break room.
Surveillance of the tow entrance and egress is accom-
(a) Number and type of operations required to be
plished by the lock operator during travels between
accomplished at the project; for example, operation of